These transformations are tied to the changing American diet. Since the early 1980s, America’s per-person cheese consumption has doubled, largely in the form of mozzarella-covered pizza pies. And last year, for the first time, the average American ate 100 pounds of chicken, twice the amount 40 years ago.
We’re already reducing population. In order to stave off disaster without atrocity we will need to accept lifestyle changes. Groundwater issues are a problem now, not in a generation. And there have been vegans and vegetarians for millennia too.
Growth is slowing, but we are far from reducing. The numbers continue to climb: https://www.census.gov/popclock/world